<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8" />
    <title>何为数据代理</title>
  </head>
  <body>
    <!-- 数据代理：通过一个对象代理对另一个对象中属性的操作（读/写）-->
    <script type="text/javascript">
      let obj = { x: 100 }
      let obj2 = { y: 200 }

      Object.defineProperty(obj2, 'x', {
        get() {
          return obj.x
        },
        set(value) {
          obj.x = value
        },
      })
    </script>
  </body>
</html>
